The company CEO stood by Apple's decision to include a 4-inch screen in the iPhone 5, pointing out that it offers quality and easy one-handed use.
"We've put a lot of thinking into screen size and we think we've picked the right one," he told reporters during the Cupertino firm's fourth-quarter earnings call.
Cook's comments come in the wake of reports from China suggesting that Apple is readying a larger version of the smartphone dubbed the 'iPhone Math' for release alongside the iPhone 5S.
Apple's latest financial results confirm that it sold a record 47.8 million iPhones and 22.9 million iPads in the three months to December 29, 2012, up from 37 million iPhones and 15.4 million iPads during the same period in 2011.
Previous reports suggest that Apple is planning to release new tablets in the coming month, with a second-generation iPad mini sporting a Retina display likely to be the first out of the bag.